1. Technical Field
The present disclosure relates generally to a display device. More particularly, the present disclosure relates to a transparent display panel that can adjust light transmittance and a transparent display device including the transparent display panel.
2. Description of the Related Art
Recently, a transparent display device (e.g., a car window, a show window, a building window) that allows a viewer to watch an object behind a transparent display panel of the transparent display device as well as visual information displayed on the transparent display panel has received attention. Generally, since incident light directly affects an image displayed on the transparent display panel in the transparent display device, quality and visibility of the image may be degraded because a contrast ratio of the image is lowered as intensity of the incident light increases. Thus, to improve the quality of the image, conventional transparent display devices may maintain the contrast ratio of the image regardless of the intensity of the incident light using a liquid crystal structure located over or under the transparent display panel and by adjusting light transmittance of the liquid crystal structure according to the intensity of the incident light. However, in the conventional transparent display devices, light transmittance may be decreased by an internal structure such as a thin film transistor, a liquid crystal layer, an upper electrode, and a lower electrode of the liquid crystal structure, and the power consumption for driving the liquid crystal structure may unnecessarily increase.